Re: [PATCH v2] xfsprogs: copy_range don't truncate dstfile

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Thu, Sep 05, 2019 at 07:36:34AM +0800, Jianhong.Yin wrote:
> now if we do copy_range from srcfile to dstfile without any option
> will truncate the dstfile, and not any document indicate this default
> action. that's unexpected and confuse people.

Needs manpage update.

Also, did you check that xfstests doesn't somehow use this?  There are
several cfr tests now...

generic/430 generic/431 generic/432 generic/433 generic/434 generic/553
generic/554 generic/564 generic/565 generic/716

--D

> '''
> $ ./xfs_io -f -c 'copy_range copy_file_range.c'  testfile
> $ ll testfile
> -rw-rw-r--. 1 yjh yjh 3534 Sep  5 07:15 testfile
> $ ./xfs_io -c 'copy_range testfile'  testfile
> $ ll testfile
> -rw-rw-r--. 1 yjh yjh 3534 Sep  5 07:16 testfile
> $ ./xfs_io -c 'copy_range testfile -l 3534 -d 3534' testfile
> $ ll testfile
> -rw-rw-r--. 1 yjh yjh 7068 Sep  5 07:17 testfile
> $ ./xfs_io -c 'copy_range copy_file_range.c'  testfile
> $ ll testfile
> -rw-rw-r--. 1 yjh yjh 7068 Sep  5 07:18 testfile
> $ cmp -n 3534 copy_file_range.c testfile
> $ cmp -i 0:3534 copy_file_range.c testfile
> '''
> 
> Signed-off-by: Jianhong Yin <yin-jianhong@163.com>
> ---
>  io/copy_file_range.c | 15 ---------------
>  1 file changed, 15 deletions(-)
> 
> diff --git a/io/copy_file_range.c b/io/copy_file_range.c
> index b7b9fd88..283f5094 100644
> --- a/io/copy_file_range.c
> +++ b/io/copy_file_range.c
> @@ -66,15 +66,6 @@ copy_src_filesize(int fd)
>  	return st.st_size;
>  }
>  
> -static int
> -copy_dst_truncate(void)
> -{
> -	int ret = ftruncate(file->fd, 0);
> -	if (ret < 0)
> -		perror("ftruncate");
> -	return ret;
> -}
> -
>  static int
>  copy_range_f(int argc, char **argv)
>  {
> @@ -146,12 +137,6 @@ copy_range_f(int argc, char **argv)
>  			goto out;
>  		}
>  		len = sz;
> -
> -		ret = copy_dst_truncate();
> -		if (ret < 0) {
> -			ret = 1;
> -			goto out;
> -		}
>  	}
>  
>  	ret = copy_file_range_cmd(fd, &src, &dst, len);
> -- 
> 2.21.0
>